.
Equivalent runway condition (if braking action and runway friction coefficient are not available).
Maximum Recommended Crosswind
Good ( 5 ) 0.40 and above Note 1 35 kt
Good / Medium ( 4 ) 0.36 to 0.39 Note 1 30 kt
Medium ( 3 ) 0.30 to 0.35 Note 2 and Note 3 25 kt
Medium / Poor ( 2 ) 0.26 to 0.29 Note 2 and Note 3 20 kt
Poor ( 1 ) 0.25 and below Note 3 and Note 4 15 kt
Unreliable ( 9 ) Unreliable Note 4 and Note 5 5 kt
Table 1
Maximum Recommended Crosswind - Typical
Crosswind Landings
Page 1
AIRBUS INDUSTRIE Getting to Grips with
Flight Operations Support Approach-and-Landing Accidents Reduction
The Equivalent Runway Condition, defined by Note 1 through Note 5, can be used only for the determination of the maximum recommended crosswind.
This Equivalent Runway Condition cannot be used for the computation of takeoff and landing performance, because it does not account for the effects of the displacement drag and impingement drag ( as defined in Briefing Note 8.5 – Landing on Wet or Contaminated Runway ).
Note 1 :
Dry, damp or wet runway (i.e., less than 3mm water depth) without risk of hydroplaning.
Note 2 :
Runway covered with slush.
Note 3 :
Runway covered with dry snow.
Note 4 :
Runway covered with standing water, with risk of hydroplaning, or with wet snow.
Note 5 :
Runway with high risk of hydroplaning.
The maximum recommended crosswind on a contaminated runway is based on computation rather than flight tests, but the calculated values are
adjusted in a conservative manner based on
operational experience.
Some operators consider reduced maximum
crosswind values when the first officer is PF, during line training and initial line operation.
The maximum crosswind for performing an autoland is a certified limitation.
Assignment by ATC of a given landing runway should be questioned by the PF if prevailing runway conditions and crosswind component are considered inadequate for a safe landing.
Final Approach Technique
Figure 1 shows that depending on the recommendations published in the aircraft-operating manual, the final approach under crosswind conditions may be conducted :
.
With wings-level (i.e., applying a drift correction in order to track the runway centerline, this type of approach is called a crabbed approach); or,
.
With a steady sideslip (i.e., with the aircraft fuselage aligned with the runway centerline, using a combination of into-wind aileron and opposite rudder to correct the drift).
Crabbed Approach Sideslip Approach
Figure 1
Crabbed Approach versus Sideslip Approach
This Briefing Note focus on the wings-level / crabbed approach technique, recommended by Airbus Industrie, to discuss the associated flare and decrab techniques depending on the crosswind component.
Crosswind Landings
Page 2
AIRBUS INDUSTRIE
Flight Operations Support
Airframe manufacturers consider the following factors when recommending a wings-level or a steady-side-slip approach :
.
Aircraft geometry (i.e., pitch attitude and bank angle limits for preventing tail strike, engine nacelle contact or wingtip contact);
.
Ailerons (roll) and rudder (yaw) authority; and,
.
Crosswind component.
Flare Technique
Approaching the flare point with wings-level and with a crab angle, as required for drift correction, three flare techniques are possible (depending on runway condition, crosswind component and company SOPs):
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